semibreve vs whole note

semibreve and whole note both are nouns.

Word	Noun	Adjective	Verb	Adverb
semibreve	Yes	No	No	No
whole note	Yes	No	No	No

As nouns, semibreve and whole note are synonyms defined as:

semibreve and whole note: a musical note having the longest time value (equal to four beats in common time)

semibreve (noun)	whole note (noun)
a musical note having the longest time value (equal to four beats in common time)	a musical note having the longest time value (equal to four beats in common time)